Governor Deval Patrick wasn’t the only one shaken by former Representative Barney Frank’s very public declaration on Friday that he’d like to serve as interim senator if John F. Kerry resigns to serve as secretary of state.

A former colleague, Representative Edward J. Markey, was rankled by the prospect, friends say, in part because of the inevitable poll that would gauge Frank’s popularity as senator. A high approval rating for Frank could overshadow Markey’s candidacy in the special election campaign that would be needed to fill the seat permanently.

In a statement today, Markey disputed feeling any discomfort over a Frank appointment, labeling the suggestion “completely false.”

Spokeswoman Giselle Barry said: “Representative Markey has full confidence that Governor Patrick will appoint the best person to represent Massachusetts before the Senate seat can be permanently filled.”

Frank and Markey share a history, as they say in life and politics, and it’s not just related to the fact that they started together the same day in 1973 in the Massachusetts Legislature, or then shared 27 years in the US House.

When the Legislature redrafted the Massachusetts congressional districts in 2011, Frank was among the members who felt Markey exploited his position as delegation dean to create a favorable district around his Malden home base, while disregarding the needs of his colleagues.

Frank’s territory was altered to pick up several conservative communities. The congressman said that change helped fuel his decision to retire last week after 32 years in Congress.

Frank, a Newton Democrat, declared again Friday that he would “absolutely not” be a candidate in the special election, even if Patrick awarded him the job on an interim basis. But he also was similarly Shermanesque about his desire to leave Congress, an opinion he has since changed.

Patrick’s preferencePatrick has already said it is his preference to not appoint an interim senator who would also be a special election candidate, believing the same person can’t effectively serve in Congress while also running a statewide political campaign.

It’s one of the reasons the governor is unlikely to give the interim appointment to a sitting congressman, which many state Democrats think would actually give the party a running start in their effort to retain the seat in the special election.

So even as the Democratic Party has coalesced around Markey, Patrick has notably withheld his endorsement. The congressman has already lined up support from Kerry; Vicki Kennedy, the widow of Senator Edward M. Kennedy; and the Democratic Senatorial Campaign Committee, the group charged with raising money for Democrats running for the Senate.

Yet by not appointing Markey, Patrick may actually be doing him a favor: leaving him free to run without having to give up his seat — or responsibilities — in Congress.

It’s exactly the scenario Patrick said he opposed.

‘Better options’ out there

On Friday, the governor paid appropriate homage to Frank, calling him a “really gifted legislator” and someone who is “definitely on the list” for an interim appointment.

On Saturday, though, Patrick’s political consigliere, Doug Rubin, very publicly raised doubts about Frank ever getting the appointment. “I respect Cong. Frank and what he has accomplished, but there are better options for MA Senate interim appointment,” Rubin said on his Twitter account.

In a subsequent interview, Rubin told the Globe that the opinion was his alone and not the governor’s, nor that of the state’s new senator, Elizabeth Warren, who also is a Rubin political client.

“The theory that we have to send experienced people to Washington to break the gridlock; the experienced people are the ones creating the gridlock,” said Rubin.

He added: “If we get beyond the traditional names, there are a lot of smart, talented individuals from Massachusetts who could bring some fresh ideas and energy to Washington, and that’s what we sorely need.”

One of the low-profile potential picks is outgoing Administration and Finance Secretary Jay Gonzalez, a trusted Patrick aide. State House insiders say another possible pick in that mold is the governor’s departing chief of staff, William “Mo” Cowan.

South Carolina Governor Nikki Haley recently appointed the Senate’s only current black member, Representative Tim Scott, to fill the vacancy created by the resignation of Senator Jim DeMint.

A Cowan appointment would double the African-American caucus, the kind of history-making for which the governor has shown a fondness.

Cowan did not respond to an e-mail seeking comment.

Frank comes back to Mass.

Immediately after declaring his interest Friday in returning to Washington, Frank headed out of the capital city.

The former congressman and his husband, Jim Ready, got in Frank’s car and drove it back to Massachusetts. Their plan was to spend the night in New Bedford, so they could participate on Saturday in the former whaling city’s annual marathon reading of “Moby Dick.”

Then, on Monday, Frank has an appointment at the Registry of Motor Vehicles.

He plans to surrender the congressional license plates that have adorned his car while he served in the House.